/**
 * Software License, Version 1.0
 * 
 * Copyright 2003 The Trustees of Indiana University.  All rights reserved.
 * 
 *
 *Redistribution and use in source and binary forms, with or without 
 *modification, are permitted provided that the following conditions are met:
 *
 *1) All redistributions of source code must retain the above copyright notice,
 * the list of authors in the original source code, this list of conditions and
 * the disclaimer listed in this license;
 *2) All redistributions in binary form must reproduce the above copyright 
 * notice, this list of conditions and the disclaimer listed in this license in
 * the documentation and/or other materials provided with the distribution;
 *3) Any documentation included with all redistributions must include the 
 * following acknowledgement:
 *
 *"This product includes software developed by the Community Grids Lab. For 
 * further information contact the Community Grids Lab at 
 * http://communitygrids.iu.edu/."
 *
 * Alternatively, this acknowledgement may appear in the software itself, and 
 * wherever such third-party acknowledgments normally appear.
 * 
 *4) The name Indiana University or Community Grids Lab or NaradaBrokering, 
 * shall not be used to endorse or promote products derived from this software 
 * without prior written permission from Indiana University.  For written 
 * permission, please contact the Advanced Research and Technology Institute 
 * ("ARTI") at 351 West 10th Street, Indianapolis, Indiana 46202.
 *5) Products derived from this software may not be called NaradaBrokering, 
 * nor may Indiana University or Community Grids Lab or NaradaBrokering appear
 * in their name, without prior written permission of ARTI.
 * 
 *
 * Indiana University provides no reassurances that the source code provided 
 * does not infringe the patent or any other intellectual property rights of 
 * any other entity.  Indiana University disclaims any liability to any 
 * recipient for claims brought by any other entity based on infringement of 
 * intellectual property rights or otherwise.  
 *
 *LICENSEE UNDERSTANDS THAT SOFTWARE IS PROVIDED "AS IS" FOR WHICH NO 
 *WARRANTIES AS TO CAPABILITIES OR ACCURACY ARE MADE. INDIANA UNIVERSITY GIVES
 *NO WARRANTIES AND MAKES NO REPRESENTATION THAT SOFTWARE IS FREE OF 
 *INFRINGEMENT OF THIRD PARTY PATENT, COPYRIGHT, OR OTHER PROPRIETARY RIGHTS. 
 *INDIANA UNIVERSITY MAKES NO WARRANTIES THAT SOFTWARE IS FREE FROM "BUGS", 
 *"VIRUSES", "TROJAN HORSES", "TRAP DOORS", "WORMS", OR OTHER HARMFUL CODE.  
 *LICENSEE ASSUMES THE ENTIRE RISK AS TO THE PERFORMANCE OF SOFTWARE AND/OR 
 *ASSOCIATED MATERIALS, AND TO THE PERFORMANCE AND VALIDITY OF INFORMATION 
 *GENERATED USING SOFTWARE.
 */
package cgl.narada.wsinfra.wsrm;

import cgl.narada.wsinfra.exception.MessageFlowException;
import cgl.narada.wsinfra.wsrm.storage.WsrmSequenceInfo;
import cgl.narada.wsinfra.wsrm.storage.WsrmStorageException;

/** This is a class which will implemented as a thread. There should be only
    one instance of this thread running per database. This would typically
    be done by ensuring that the configuration files passed during the
    initializations are different for different configFiles.

    @author Shrideep Pallickara
    $Date: 2005/01/06 23:17:27 $
    $Revision: 1.1 $
*/

public interface WsrmSequenceMonitor {

  /** Begin services related to sequence monitoring viz. issue acknowledgements
      and initiate retransmissions for sequences. */
  public void startServices();

  /** Stop services related to sequence monitoring. */
  public void stopServices();

  /** Checks to see if the inactivity interval has expired on the
      sequence in question. */
  public boolean checkInactivityTimeout(WsrmSequenceInfo wsrmSequenceInfo) 
    throws WsrmStorageException;
  
  
  /** Checks to see if any messages have been stored for this sequence in
      question. */
  public boolean checkIfMessagesAvailable(WsrmSequenceInfo wsrmSequenceInfo)
    throws WsrmStorageException;


  /** This method checks to see if acknowledgements should be issued on
      a specific sequence. If there is a neeed to do so, it proceeds to 
      issue acknowledgements on the sequence. */
  public void checkToIssueAcknowledgements(WsrmSequenceInfo wsrmSequenceInfo)
    throws MessageFlowException, WsrmStorageException;

  
  /** This method checks to see if retransmissions need to be issued on the
      specified sequence. If a need arises retransmissions are issued and
      the retransmission interval is reset. There should also be a way to
      ensure exponential backoff. */
  public void checkToIssueRetransmissions(WsrmSequenceInfo wsrmSequenceInfo) 
    throws WsrmStorageException, MessageFlowException;
}
